1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26 /*
  27  * Copyright (c) 2018, Joyent, Inc.
  28  */
  29 
  30 /*
  31  * User Process Target Intel 32-bit component
  32  *
  33  * This file provides the ISA-dependent portion of the user process target.
  34  * For more details on the implementation refer to mdb_proc.c.
  35  */
  36 
  37 #include <mdb/mdb_proc.h>
  38 #include <mdb/mdb_kreg.h>
  39 #include <mdb/mdb_err.h>
  40 #include <mdb/mdb_ia32util.h>
  41 #include <mdb/mdb.h>
  42 
  43 #include <sys/ucontext.h>
  44 #include <sys/frame.h>
  45 #include <libproc.h>
  46 #include <sys/fp.h>
  47 #include <ieeefp.h>
  48 
  49 #include <stddef.h>
  50 
  51 const mdb_tgt_regdesc_t pt_regdesc[] = {
  52         { "gs", GS, MDB_TGT_R_EXPORT },
  53         { "fs", FS, MDB_TGT_R_EXPORT },
  54         { "es", ES, MDB_TGT_R_EXPORT },
  55         { "ds", DS, MDB_TGT_R_EXPORT },
  56         { "edi", EDI, MDB_TGT_R_EXPORT },
  57         { "di", EDI, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
  58         { "esi", ESI, MDB_TGT_R_EXPORT },
  59         { "si", ESI, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
  60         { "ebp", EBP, MDB_TGT_R_EXPORT },
  61         { "bp", EBP, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
  62         { "kesp", ESP, MDB_TGT_R_EXPORT },
  63         { "ksp", ESP, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
  64         { "ebx", EBX, MDB_TGT_R_EXPORT },
  65         { "bx", EBX, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
  66         { "bh", EBX, MDB_TGT_R_EXPORT | MDB_TGT_R_8H },
  67         { "bl", EBX, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
  68         { "edx", EDX, MDB_TGT_R_EXPORT },
  69         { "dx", EDX, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
  70         { "dh", EDX, MDB_TGT_R_EXPORT | MDB_TGT_R_8H },
  71         { "dl", EDX, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
  72         { "ecx", ECX, MDB_TGT_R_EXPORT },
  73         { "cx", ECX, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
  74         { "ch", ECX, MDB_TGT_R_EXPORT | MDB_TGT_R_8H },
  75         { "cl", ECX, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
  76         { "eax", EAX, MDB_TGT_R_EXPORT },
  77         { "ax", EAX, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
  78         { "ah", EAX, MDB_TGT_R_EXPORT | MDB_TGT_R_8H },
  79         { "al", EAX, MDB_TGT_R_EXPORT | MDB_TGT_R_8L },
  80         { "trapno", TRAPNO, MDB_TGT_R_EXPORT },
  81         { "err", ERR, MDB_TGT_R_EXPORT },
  82         { "eip", EIP, MDB_TGT_R_EXPORT },
  83         { "cs", CS, MDB_TGT_R_EXPORT },
  84         { "eflags", EFL, MDB_TGT_R_EXPORT },
  85         { "esp", UESP, MDB_TGT_R_EXPORT },
  86         { "sp", UESP, MDB_TGT_R_EXPORT | MDB_TGT_R_16 },
  87         { "ss", SS, MDB_TGT_R_EXPORT },
  88         { NULL, 0, 0 }
  89 };
  90 
  91 /*
  92  * We cannot rely on pr_instr, because if we hit a breakpoint or the user has
  93  * artifically modified memory, it will no longer be correct.
  94  */
  95 static uint8_t
  96 pt_read_instr(mdb_tgt_t *t)
  97 {
  98         const lwpstatus_t *psp = &Pstatus(t->t_pshandle)->pr_lwp;
  99         uint8_t ret = 0;
 100 
 101         (void) mdb_tgt_vread(t, &ret, sizeof (ret), psp->pr_reg[EIP]);
 102 
 103         return (ret);
 104 }
 105 
 106 /*ARGSUSED*/
 107 int
 108 pt_regs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
 109 {
 110         mdb_tgt_t *t = mdb.m_target;
 111         mdb_tgt_tid_t tid;
 112         prgregset_t grs;
 113         prgreg_t eflags;
 114         boolean_t from_ucontext = B_FALSE;
 115 
 116         if (mdb_getopts(argc, argv,
 117             'u', MDB_OPT_SETBITS, B_TRUE, &from_ucontext, NULL) != argc) {
 118                 return (DCMD_USAGE);
 119         }
 120 
 121         if (from_ucontext) {
 122                 int off;
 123                 int o0, o1;
 124 
 125                 if (!(flags & DCMD_ADDRSPEC)) {
 126                         mdb_warn("-u requires a ucontext_t address\n");
 127                         return (DCMD_ERR);
 128                 }
 129 
 130                 o0 = mdb_ctf_offsetof_by_name("ucontext_t", "uc_mcontext");
 131                 o1 = mdb_ctf_offsetof_by_name("mcontext_t", "gregs");
 132                 if (o0 == -1 || o1 == -1) {
 133                         off = offsetof(ucontext_t, uc_mcontext) +
 134                             offsetof(mcontext_t, gregs);
 135                 } else {
 136                         off = o0 + o1;
 137                 }
 138 
 139                 if (mdb_vread(&grs, sizeof (grs), addr + off) != sizeof (grs)) {
 140                         mdb_warn("failed to read from ucontext_t %p", addr);
 141                         return (DCMD_ERR);
 142                 }
 143                 goto print_regs;
 144         }
 145 
 146         if (t->t_pshandle == NULL || Pstate(t->t_pshandle) == PS_UNDEAD) {
 147                 mdb_warn("no process active\n");
 148                 return (DCMD_ERR);
 149         }
 150 
 151         if (Pstate(t->t_pshandle) == PS_LOST) {
 152                 mdb_warn("debugger has lost control of process\n");
 153                 return (DCMD_ERR);
 154         }
 155 
 156         if (flags & DCMD_ADDRSPEC)
 157                 tid = (mdb_tgt_tid_t)addr;
 158         else
 159                 tid = PTL_TID(t);
 160 
 161         if (PTL_GETREGS(t, tid, grs) != 0) {
 162                 mdb_warn("failed to get current register set");
 163                 return (DCMD_ERR);
 164         }
 165 
 166 print_regs:
 167         eflags = grs[EFL];
 168 
 169         mdb_printf("%%cs = 0x%04x\t\t%%eax = 0x%0?p %A\n",
 170             grs[CS], grs[EAX], grs[EAX]);
 171 
 172         mdb_printf("%%ds = 0x%04x\t\t%%ebx = 0x%0?p %A\n",
 173             grs[DS], grs[EBX], grs[EBX]);
 174 
 175         mdb_printf("%%ss = 0x%04x\t\t%%ecx = 0x%0?p %A\n",
 176             grs[SS], grs[ECX], grs[ECX]);
 177 
 178         mdb_printf("%%es = 0x%04x\t\t%%edx = 0x%0?p %A\n",
 179             grs[ES], grs[EDX], grs[EDX]);
 180 
 181         mdb_printf("%%fs = 0x%04x\t\t%%esi = 0x%0?p %A\n",
 182             grs[FS], grs[ESI], grs[ESI]);
 183 
 184         mdb_printf("%%gs = 0x%04x\t\t%%edi = 0x%0?p %A\n\n",
 185             grs[GS], grs[EDI], grs[EDI]);
 186 
 187         mdb_printf(" %%eip = 0x%0?p %A\n", grs[EIP], grs[EIP]);
 188         mdb_printf(" %%ebp = 0x%0?p\n", grs[EBP]);
 189         mdb_printf("%%kesp = 0x%0?p\n\n", grs[ESP]);
 190         mdb_printf("%%eflags = 0x%08x\n", eflags);
 191 
 192         mdb_printf("  id=%u vip=%u vif=%u ac=%u vm=%u rf=%u nt=%u iopl=0x%x\n",
 193             (eflags & KREG_EFLAGS_ID_MASK) >> KREG_EFLAGS_ID_SHIFT,
 194             (eflags & KREG_EFLAGS_VIP_MASK) >> KREG_EFLAGS_VIP_SHIFT,
 195             (eflags & KREG_EFLAGS_VIF_MASK) >> KREG_EFLAGS_VIF_SHIFT,
 196             (eflags & KREG_EFLAGS_AC_MASK) >> KREG_EFLAGS_AC_SHIFT,
 197             (eflags & KREG_EFLAGS_VM_MASK) >> KREG_EFLAGS_VM_SHIFT,
 198             (eflags & KREG_EFLAGS_RF_MASK) >> KREG_EFLAGS_RF_SHIFT,
 199             (eflags & KREG_EFLAGS_NT_MASK) >> KREG_EFLAGS_NT_SHIFT,
 200             (eflags & KREG_EFLAGS_IOPL_MASK) >> KREG_EFLAGS_IOPL_SHIFT);
 201 
 202         mdb_printf("  status=<%s,%s,%s,%s,%s,%s,%s,%s,%s>\n\n",
 203             (eflags & KREG_EFLAGS_OF_MASK) ? "OF" : "of",
 204             (eflags & KREG_EFLAGS_DF_MASK) ? "DF" : "df",
 205             (eflags & KREG_EFLAGS_IF_MASK) ? "IF" : "if",
 206             (eflags & KREG_EFLAGS_TF_MASK) ? "TF" : "tf",
 207             (eflags & KREG_EFLAGS_SF_MASK) ? "SF" : "sf",
 208             (eflags & KREG_EFLAGS_ZF_MASK) ? "ZF" : "zf",
 209             (eflags & KREG_EFLAGS_AF_MASK) ? "AF" : "af",
 210             (eflags & KREG_EFLAGS_PF_MASK) ? "PF" : "pf",
 211             (eflags & KREG_EFLAGS_CF_MASK) ? "CF" : "cf");
 212 
 213         mdb_printf("   %%esp = 0x%0?x\n", grs[UESP]);
 214         mdb_printf("%%trapno = 0x%x\n", grs[TRAPNO]);
 215         mdb_printf("   %%err = 0x%x\n", grs[ERR]);
 216 
 217         return (DCMD_OK);
 218 }
 219 
 220 static const char *
 221 fpcw2str(uint32_t cw, char *buf, size_t nbytes)
 222 {
 223         char *end = buf + nbytes;
 224         char *p = buf;
 225 
 226         buf[0] = '\0';
 227 
 228         /*
 229          * Decode all masks in the 80387 control word.
 230          */
 231         if (cw & FPIM)
 232                 p += mdb_snprintf(p, (size_t)(end - p), "|IM");
 233         if (cw & FPDM)
 234                 p += mdb_snprintf(p, (size_t)(end - p), "|DM");
 235         if (cw & FPZM)
 236                 p += mdb_snprintf(p, (size_t)(end - p), "|ZM");
 237         if (cw & FPOM)
 238                 p += mdb_snprintf(p, (size_t)(end - p), "|OM");
 239         if (cw & FPUM)
 240                 p += mdb_snprintf(p, (size_t)(end - p), "|UM");
 241         if (cw & FPPM)
 242                 p += mdb_snprintf(p, (size_t)(end - p), "|PM");
 243         if (cw & FPPC)
 244                 p += mdb_snprintf(p, (size_t)(end - p), "|PC");
 245         if (cw & FPRC)
 246                 p += mdb_snprintf(p, (size_t)(end - p), "|RC");
 247         if (cw & FPIC)
 248                 p += mdb_snprintf(p, (size_t)(end - p), "|IC");
 249 
 250         /*
 251          * Decode precision, rounding, and infinity options in control word.
 252          */
 253         if (cw & FPSIG53)
 254                 p += mdb_snprintf(p, (size_t)(end - p), "|SIG53");
 255         if (cw & FPSIG64)
 256                 p += mdb_snprintf(p, (size_t)(end - p), "|SIG64");
 257 
 258         if ((cw & FPRC) == (FPRD|FPRU))
 259                 p += mdb_snprintf(p, (size_t)(end - p), "|RTZ");
 260         else if (cw & FPRD)
 261                 p += mdb_snprintf(p, (size_t)(end - p), "|RD");
 262         else if (cw & FPRU)
 263                 p += mdb_snprintf(p, (size_t)(end - p), "|RU");
 264         else
 265                 p += mdb_snprintf(p, (size_t)(end - p), "|RTN");
 266 
 267         if (cw & FPA)
 268                 p += mdb_snprintf(p, (size_t)(end - p), "|A");
 269         else
 270                 p += mdb_snprintf(p, (size_t)(end - p), "|P");
 271         if (cw & WFPB17)
 272                 p += mdb_snprintf(p, (size_t)(end - p), "|WFPB17");
 273         if (cw & WFPB24)
 274                 p += mdb_snprintf(p, (size_t)(end - p), "|WFPB24");
 275 
 276         if (buf[0] == '|')
 277                 return (buf + 1);
 278 
 279         return ("0");
 280 }
 281 
 282 static const char *
 283 fpsw2str(uint32_t cw, char *buf, size_t nbytes)
 284 {
 285         char *end = buf + nbytes;
 286         char *p = buf;
 287 
 288         buf[0] = '\0';
 289 
 290         /*
 291          * Decode all masks in the 80387 status word.
 292          */
 293         if (cw & FPS_IE)
 294                 p += mdb_snprintf(p, (size_t)(end - p), "|IE");
 295         if (cw & FPS_DE)
 296                 p += mdb_snprintf(p, (size_t)(end - p), "|DE");
 297         if (cw & FPS_ZE)
 298                 p += mdb_snprintf(p, (size_t)(end - p), "|ZE");
 299         if (cw & FPS_OE)
 300                 p += mdb_snprintf(p, (size_t)(end - p), "|OE");
 301         if (cw & FPS_UE)
 302                 p += mdb_snprintf(p, (size_t)(end - p), "|UE");
 303         if (cw & FPS_PE)
 304                 p += mdb_snprintf(p, (size_t)(end - p), "|PE");
 305         if (cw & FPS_SF)
 306                 p += mdb_snprintf(p, (size_t)(end - p), "|SF");
 307         if (cw & FPS_ES)
 308                 p += mdb_snprintf(p, (size_t)(end - p), "|ES");
 309         if (cw & FPS_C0)
 310                 p += mdb_snprintf(p, (size_t)(end - p), "|C0");
 311         if (cw & FPS_C1)
 312                 p += mdb_snprintf(p, (size_t)(end - p), "|C1");
 313         if (cw & FPS_C2)
 314                 p += mdb_snprintf(p, (size_t)(end - p), "|C2");
 315         if (cw & FPS_C3)
 316                 p += mdb_snprintf(p, (size_t)(end - p), "|C3");
 317         if (cw & FPS_B)
 318                 p += mdb_snprintf(p, (size_t)(end - p), "|B");
 319 
 320         if (buf[0] == '|')
 321                 return (buf + 1);
 322 
 323         return ("0");
 324 }
 325 
 326 static const char *
 327 fpmxcsr2str(uint32_t mxcsr, char *buf, size_t nbytes)
 328 {
 329         char *end = buf + nbytes;
 330         char *p = buf;
 331 
 332         buf[0] = '\0';
 333 
 334         /*
 335          * Decode the MXCSR word
 336          */
 337         if (mxcsr & SSE_IE)
 338                 p += mdb_snprintf(p, (size_t)(end - p), "|IE");
 339         if (mxcsr & SSE_DE)
 340                 p += mdb_snprintf(p, (size_t)(end - p), "|DE");
 341         if (mxcsr & SSE_ZE)
 342                 p += mdb_snprintf(p, (size_t)(end - p), "|ZE");
 343         if (mxcsr & SSE_OE)
 344                 p += mdb_snprintf(p, (size_t)(end - p), "|OE");
 345         if (mxcsr & SSE_UE)
 346                 p += mdb_snprintf(p, (size_t)(end - p), "|UE");
 347         if (mxcsr & SSE_PE)
 348                 p += mdb_snprintf(p, (size_t)(end - p), "|PE");
 349 
 350         if (mxcsr & SSE_DAZ)
 351                 p += mdb_snprintf(p, (size_t)(end - p), "|DAZ");
 352 
 353         if (mxcsr & SSE_IM)
 354                 p += mdb_snprintf(p, (size_t)(end - p), "|IM");
 355         if (mxcsr & SSE_DM)
 356                 p += mdb_snprintf(p, (size_t)(end - p), "|DM");
 357         if (mxcsr & SSE_ZM)
 358                 p += mdb_snprintf(p, (size_t)(end - p), "|ZM");
 359         if (mxcsr & SSE_OM)
 360                 p += mdb_snprintf(p, (size_t)(end - p), "|OM");
 361         if (mxcsr & SSE_UM)
 362                 p += mdb_snprintf(p, (size_t)(end - p), "|UM");
 363         if (mxcsr & SSE_PM)
 364                 p += mdb_snprintf(p, (size_t)(end - p), "|PM");
 365 
 366         if ((mxcsr & SSE_RC) == (SSE_RD|SSE_RU))
 367                 p += mdb_snprintf(p, (size_t)(end - p), "|RTZ");
 368         else if (mxcsr & SSE_RD)
 369                 p += mdb_snprintf(p, (size_t)(end - p), "|RD");
 370         else if (mxcsr & SSE_RU)
 371                 p += mdb_snprintf(p, (size_t)(end - p), "|RU");
 372         else
 373                 p += mdb_snprintf(p, (size_t)(end - p), "|RTN");
 374 
 375         if (mxcsr & SSE_FZ)
 376                 p += mdb_snprintf(p, (size_t)(end - p), "|FZ");
 377 
 378         if (buf[0] == '|')
 379                 return (buf + 1);
 380         return ("0");
 381 }
 382 
 383 /*ARGSUSED*/
 384 int
 385 pt_fpregs(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
 386 {
 387         mdb_tgt_t *t = mdb.m_target;
 388         mdb_tgt_tid_t tid;
 389         uint32_t hw = FP_NO;
 390         uint_t sse = 0;
 391         prfpregset_t fprs;
 392         struct _fpstate fps;
 393         char buf[256];
 394         uint_t top;
 395         int i;
 396 
 397         /*
 398          * Union for overlaying _fpreg structure on to quad-precision
 399          * floating-point value (long double).
 400          */
 401         union {
 402                 struct _fpreg reg;
 403                 long double ld;
 404         } fpru;
 405 
 406         /*
 407          * Array of strings corresponding to FPU tag word values (see
 408          * section 7.3.6 of the Intel Programmer's Reference Manual).
 409          */
 410         const char *tag_strings[] = { "valid", "zero", "special", "empty" };
 411 
 412         if (argc != 0)
 413                 return (DCMD_USAGE);
 414 
 415         if (t->t_pshandle == NULL || Pstate(t->t_pshandle) == PS_UNDEAD) {
 416                 mdb_warn("no process active\n");
 417                 return (DCMD_ERR);
 418         }
 419 
 420         if (Pstate(t->t_pshandle) == PS_LOST) {
 421                 mdb_warn("debugger has lost control of process\n");
 422                 return (DCMD_ERR);
 423         }
 424 
 425         if (flags & DCMD_ADDRSPEC)
 426                 tid = (mdb_tgt_tid_t)addr;
 427         else
 428                 tid = PTL_TID(t);
 429 
 430         if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &hw,
 431             sizeof (hw), "libc.so", "_fp_hw") < 0 &&
 432             mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &hw,
 433             sizeof (hw), MDB_TGT_OBJ_EXEC, "_fp_hw") < 0)
 434                 mdb_warn("failed to read _fp_hw value");
 435 
 436         if (mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &sse,
 437             sizeof (sse), "libc.so", "_sse_hw") < 0 &&
 438             mdb_tgt_readsym(t, MDB_TGT_AS_VIRT, &sse,
 439             sizeof (sse), MDB_TGT_OBJ_EXEC, "_sse_hw") < 0)
 440                 mdb_warn("failed to read _sse_hw value");
 441 
 442         mdb_printf("_fp_hw 0x%02x (", hw);
 443         switch (hw) {
 444         case FP_SW:
 445                 mdb_printf("80387 software emulator");
 446                 break;
 447         case FP_287:
 448                 mdb_printf("80287 chip");
 449                 break;
 450         case FP_387:
 451                 mdb_printf("80387 chip");
 452                 break;
 453         case FP_486:
 454                 mdb_printf("80486 chip");
 455                 break;
 456         default:
 457                 mdb_printf("no floating point support");
 458                 break;
 459         }
 460         if (sse)
 461                 mdb_printf(" with SSE");
 462         mdb_printf(")\n");
 463 
 464         if (!(hw & FP_HW))
 465                 return (DCMD_OK); /* just abort if no hardware present */
 466 
 467         if (PTL_GETFPREGS(t, tid, &fprs) != 0) {
 468                 mdb_warn("failed to get floating point registers");
 469                 return (DCMD_ERR);
 470         }
 471 
 472         bcopy(&fprs.fp_reg_set.fpchip_state, &fps, sizeof (fps));
 473 
 474         fps.cw &= 0xffff;   /* control word is really 16 bits */
 475         fps.sw &= 0xffff;   /* status word is really 16 bits */
 476         fps.status &= 0xffff;       /* saved status word is really 16 bits */
 477         fps.cssel &= 0xffff;        /* %cs is really 16-bits */
 478         fps.datasel &= 0xffff;      /* %ds is really 16-bits too */
 479 
 480         mdb_printf("cw     0x%04x (%s)\n", fps.cw,
 481             fpcw2str(fps.cw, buf, sizeof (buf)));
 482 
 483         top = (fps.sw & FPS_TOP) >> 11;
 484         mdb_printf("sw     0x%04x (TOP=0t%u) (%s)\n", fps.sw,
 485             top, fpsw2str(fps.sw, buf, sizeof (buf)));
 486 
 487         mdb_printf("xcp sw 0x%04x (%s)\n\n", fps.status,
 488             fpsw2str(fps.status, buf, sizeof (buf)));
 489 
 490         mdb_printf("ipoff  %a\n", fps.ipoff);
 491         mdb_printf("cssel  0x%x\n", fps.cssel);
 492         mdb_printf("dtoff  %a\n", fps.dataoff);
 493         mdb_printf("dtsel  0x%x\n\n", fps.datasel);
 494 
 495         for (i = 0; i < 8; i++) {
 496                 /*
 497                  * Recall that we need to use the current TOP-of-stack value to
 498                  * associate the _st[] index back to a physical register number,
 499                  * since tag word indices are physical register numbers.  Then
 500                  * to get the tag value, we shift over two bits for each tag
 501                  * index, and then grab the bottom two bits.
 502                  */
 503                 uint_t tag_index = (i + top) & 7;
 504                 uint_t tag_value = (fps.tag >> (tag_index * 2)) & 3;
 505 
 506                 fpru.reg = fps._st[i];
 507                 mdb_printf("%%st%d   0x%04x.%04x%04x%04x%04x = %lg %s\n",
 508                     i, fpru.reg.exponent,
 509                     fpru.reg.significand[3], fpru.reg.significand[2],
 510                     fpru.reg.significand[1], fpru.reg.significand[0],
 511                     fpru.ld, tag_strings[tag_value]);
 512         }
 513 
 514         if (!sse)
 515                 return (DCMD_OK);
 516 
 517         mdb_printf("\nmxcsr  0x%04x (%s)\n", fps.mxcsr,
 518             fpmxcsr2str(fps.mxcsr, buf, sizeof (buf)));
 519         mdb_printf("xcp    0x%04x (%s)\n\n", fps.xstatus,
 520             fpmxcsr2str(fps.xstatus, buf, sizeof (buf)));
 521 
 522         for (i = 0; i < 8; i++)
 523                 mdb_printf("%%xmm%d  0x%08x%08x%08x%08x\n", i,
 524                     fps.xmm[i][3], fps.xmm[i][2],
 525                     fps.xmm[i][1], fps.xmm[i][0]);
 526 
 527         return (DCMD_OK);
 528 }
 529 
 530 /*ARGSUSED*/
 531 int
 532 pt_getfpreg(mdb_tgt_t *t, mdb_tgt_tid_t tid, ushort_t rd_num,
 533     ushort_t rd_flags, mdb_tgt_reg_t *rp)
 534 {
 535         return (set_errno(ENOTSUP));
 536 }
 537 
 538 /*ARGSUSED*/
 539 int
 540 pt_putfpreg(mdb_tgt_t *t, mdb_tgt_tid_t tid, ushort_t rd_num,
 541     ushort_t rd_flags, mdb_tgt_reg_t rval)
 542 {
 543         return (set_errno(ENOTSUP));
 544 }
 545 
 546 /*ARGSUSED*/
 547 void
 548 pt_addfpregs(mdb_tgt_t *t)
 549 {
 550         /* not implemented */
 551 }
 552 
 553 /*ARGSUSED*/
 554 int
 555 pt_frameregs(void *arglim, uintptr_t pc, uint_t argc, const long *argv,
 556     const mdb_tgt_gregset_t *gregs, boolean_t pc_faked)
 557 {
 558         return (set_errno(ENOTSUP));
 559 }
 560 
 561 /*ARGSUSED*/
 562 const char *
 563 pt_disasm(const GElf_Ehdr *ehp)
 564 {
 565         return ("ia32");
 566 }
 567 
 568 /*
 569  * Determine the return address for the current frame.
 570  */
 571 int
 572 pt_step_out(mdb_tgt_t *t, uintptr_t *p)
 573 {
 574         const lwpstatus_t *psp = &Pstatus(t->t_pshandle)->pr_lwp;
 575 
 576         if (Pstate(t->t_pshandle) != PS_STOP)
 577                 return (set_errno(EMDB_TGTBUSY));
 578 
 579         return (mdb_ia32_step_out(t, p, psp->pr_reg[EIP], psp->pr_reg[EBP],
 580             psp->pr_reg[UESP], pt_read_instr(t)));
 581 }
 582 
 583 /*
 584  * Return the address of the next instruction following a call, or return -1
 585  * and set errno to EAGAIN if the target should just single-step.
 586  */
 587 int
 588 pt_next(mdb_tgt_t *t, uintptr_t *p)
 589 {
 590         const lwpstatus_t *psp = &Pstatus(t->t_pshandle)->pr_lwp;
 591 
 592         if (Pstate(t->t_pshandle) != PS_STOP)
 593                 return (set_errno(EMDB_TGTBUSY));
 594 
 595         return (mdb_ia32_next(t, p, psp->pr_reg[EIP], pt_read_instr(t)));
 596 }